Hospital bed

ABSTRACT

A patient support apparatus including a patient support and a powered transport device to facilitate movement of a patient support.

This application is a continuation of U.S. patent application Ser. No.11/322,747, filed Dec. 30, 2005, which is a continuation of U.S. patentapplication Ser. No. 10/832,599, filed Apr. 27, 2004, which is acontinuation of U.S. patent application Ser. No. 10/195,981, filed Jul.16, 2002, now U.S. Pat. No. 6,725,474, which is a continuation of U.S.patent application Ser. No. 10/085,855, filed Feb. 28, 2002, now U.S.Pat. No. 6,694,548, which is a continuation of U.S. patent applicationSer. No. 09/655,525, filed Sep. 5, 2000, now U.S. Pat. No. 6,374,436,which is a continuation of U.S. patent application Ser. No. 09/370,272,filed Aug. 9, 1999, now U.S. Pat. No. 6,112,345, which is a divisionalof U.S. patent application Ser. No. 09/009,522, filed Jan. 20, 1998, nowU.S. Pat. No. 5,933,888, which is a divisional of U.S. patentapplication Ser. No. 08/755,480, filed Nov. 22, 1996, now U.S. Pat. No.5,708,997, which is a divisional of U.S. patent application Ser. No.08/277,243, filed Jul. 19, 1994, now U.S. Pat. No. 5,577,279, which is acontinuation in part of U.S. patent application Ser. No. 08/234,403,filed Apr. 28, 1994, now U.S. Pat. No. 5,454,126, which is acontinuation in part of U.S. patent application Ser. No. 08/186,657,filed Jan. 25, 1994, now U.S. Pat. No. 5,479,666, and a continuation inpart of U.S. patent application Ser. No. 08/230,061, filed Apr. 21,1994, now U.S. Pat. No. 5,513,406, which is a continuation in part ofU.S. patent application Ser. No. 08/186,657, filed Jan. 25, 1994, nowU.S. Pat. No. 5,479,666, all of which are hereby incorporated byreference herein as if fully set forth in their entirety. Thedisclosures of U.S. Pat. Nos. 5,672,849; 5,483,709; 5,337,845;5,335,651; 5,370,111; and 5,117,521 are hereby incorporated by referenceherein as if fully set forth in their entirety.

BACKGROUND AND SUMMARY OF THE INVENTION

This invention relates generally to patient support apparatus, and moreparticularly to patient support apparatus which include a poweredtransport device to facilitate movement of a patient support.

According to one aspect of the present invention, a patient supportapparatus is provided. The patient support apparatus includes a patientsupport and a powered transport device. The powered transport deviceincludes a wheel and a motor coupled to the wheel to power rotation ofthe wheel. The wheel is in contact with the floor to facilitate movementof the patient support when rotated by the motor.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description particularly refers to the accompanying figuresin which:

FIG. 1 is a perspective view of the present disclosure with theventilator in its high position and separated from the hospital bed baseand connected to AC wall outlets;

FIG. 2 is a view similar to FIG. 1 but illustrating the ventilator inits low position and docked to the hospital bed base and powered by thebed power supply;

FIG. 3 is a schematic view taken along line 3 of FIG. 2 and illustratingone mechanism for raising and lowering the ventilator on the ventilatorcart, the mechanism being shown in a lowered position;

FIG. 4 illustrates another embodiment of the ventilator cart of thepresent disclosure;

FIG. 5 is a view taken along line 5 of FIG. 4;

FIG. 6 is a perspective view of the care cart of the present disclosure;

FIG. 7 is a perspective view of the care cart docking to a hospital bed;

FIG. 8 is a perspective view of the care cart docked to a hospital bed;

FIG. 9 is a perspective view of another embodiment of the care cart ofthe present disclosure;

FIG. 10 is a perspective view of the care cart of FIG. 9 with doorsopened and access cover removed;

FIG. 11 is a perspective view of yet another embodiment of the care cartincorporating a motorized pilot jack therewith;

FIG. 12 is a perspective view of the motorized transport of the presentdisclosure docked to the head end of the hospital bed and with the carecart docked to the foot end of the hospital bed;

FIG. 13 is an enlarged, partial perspective view of the motorizedtransport approaching the y-shaped hospital bed base for dockingthereto;

FIG. 14 is a partial side elevational view, in partial cross-section, ofthe motorized transport approaching the hospital bed base for dockingthereto;

FIG. 15 is a partial side elevational view, in partial cross-section, ofthe motorized transport in the initial stage of docking to the hospitalbed base;

FIG. 16 is a partial side elevational view, in partial cross-section, ofthe latching fingers of the motorized transport latched to the hospitalbed mounting block in the final stage of docking to the bed base;

FIG. 17 is a partial side elevational view, in partial cross-section, ofthe motorized transport being released from the hospital bed base;

FIG. 18 is a top plan view of the front end of the motorized transport;

FIG. 19 is a partial front elevational view of the motorized transport;and

FIG. 20 is a view taken along line 20-20 of FIG. 19.

DETAILED DESCRIPTION OF THE DRAWINGS

With reference to the drawings, and first to FIGS. 1 and 2, there isillustrated a critical care environment designated generally by thenumeral 2 for providing care to a critically ill patient 4. The standardcritical care environment 2 includes, generally, a critical care bedassembly 10, and a mobile ventilator assembly 12. Other critical careequipment such as I.V. pumps, various monitors, and one or moreterminals for entering patient care data, are also typically present inthis environment but are not shown in the drawings for clarity purposes.

The mobile ventilator assembly 12 includes a ventilator cart 18 having abase 20 to which are mounted wheels or casters 22. Extending upwardlyfrom the base 20 are a pair of uprights 24, 24 for supporting aventilator 26. The ventilator 26 includes a control panel 28 and a flatpanel display 30 for monitoring the ventilator 26. The ventilator 26includes cables 32, 32 to supply power from suitable AC outlets 34, 34mounted on a wall 36 of a critical care hospital room. The ventilator 26is tethered to the patient 4 via hoses 38, 38.

Referring to FIG. 1, the ventilator 26 is illustrated in its upwardmostposition where it is approximately beside height thereby facilitatingoperation of the ventilator 26 by a care provider by placing controlpanel 28 and display 30 at a convenient height.

With reference to FIG. 2, it will be noted that the ventilator 26 islowered and positioned in a downwardmost compact configuration in orderto be docked with the critical care bed assembly 10 for transportingboth the bed assembly 10 and ventilator assembly 12 as a unit. In orderto raise and lower the ventilator 26, each support 24 is provided withan adjusting mechanism 40 which allows for selectively raising andlowering the ventilator 26 on the supports 24. While most any suitablemechanism 40 could be utilized, one such adjusting mechanism 40 isillustrated in FIG. 3. Each mechanism 40 includes a generally box shapedsleeve 42 mounted for vertical sliding movement on its respectivesupport 24. The sleeve 42 is fixedly secured to an external wall 44 ofthe ventilator 26 as by screws 46. Mounted internally of the support 24is an air spring assembly 48. Air spring assembly 40 includes anelongated air tight plenum 60 fixedly secured by bolts 61 to the base 20of cart 18. A coil spring 62 resides in the bottom of the plenum 60 andprovides assistance in lifting the weight of the ventilator 26 whenadjusting the ventilator from the low position to the high position. Thecoil spring 62 acts upon a block or piston 64 which is fixedly securedto the lower end of a hollow cylinder or piston rod 66. The upper end ofcylinder 66 is connected to the sleeve 42 via a bracket 68. Containedwithin the cylinder 66 is a rod 70 which extends downwardly through anaperture 72 in the block 64 and has on its lower end a valve 74 whichseats against the lower side of the block 64. The upper end of rod 70 isadapted to be moved vertically by a pivotable lever 76 which itself isan extension of a handle 78 mounted to sleeve 42 via a bracket 80. Tofacilitate this vertical movement of sleeve 42 and hence lever 76, theuprights 24 have a vertical slot 79 through which the bracket 68extends. Block 64 includes around its periphery a suitable seal 90 toprevent air from transferring between the two cavities of plenum 60defined by the block 64. A seal 92 is utilized at the upper end ofplenum 60 to allow the cylinder 66 to travel vertically with respect tothe plenum 60 without loss of air therefrom.

It will be appreciated that upward motion of handle 78 causes downwardmotion of lever 76, the end of which contacts the upper end of rod 70.Continued upward motion of handle 78 causes the lever 76 to force rod 70downwardly causing valve 74 to unseat from the lower surface of block64. Rod 70 is spring loaded with respect to cylinder 66 internally bymeans not shown, such that when handle 78 is released, lever 76 risesthereby releasing rod 70, which then returns to its normal state withvalve 74 seated against the lower surface of block 64. The handle 78may, if desired, also be spring biased to a released position shown butit is anticipated that the weight of handle 78 will overcome the weightof lever 76 and release itself by gravity.

When handle 78 is raised upwardly thereby depressing the upper end ofrod 70 downwardly by virtue of the lever 76, it will be appreciated thatair may freely travel through ports 71 in cylinder 66 and aperture 72 inblock 64 to equalize the volume of air on both the upper and lower sidesof the block 64. As handle 78 is additionally raised upwardly, sleeve 42slides upwardly on post 24 and cylinder 70 and block 64 slide upwardlywithin plenum 60. Air volume is thereby equalized on either side of theblock 64. When the ventilator 26 has been moved into its desired upwardposition, handle 78 is released, thereby causing valve 74 to reseat, thevolume of air trapped therebelow by virtue of block 64 and seal 90preventing the weight of the ventilator 26 from moving it downwardly. Ofcourse, the force of coil spring 62 aids in overcoming the weight of theventilator 26 when raising same, and must be overcome by downward forceon the ventilator 26 when moving same downwardly.

Many other devices and mechanisms could similarly be employed to raiseand lower the ventilator 26 on supports 24, and the invention is notlimited to the specific embodiment illustrated, as same is only forillustrative purposes. Furthermore, such a device or mechanism could aseasily be foot operated rather than hand operated.

Referring back now to FIGS. 1 and 2, the critical care bed assembly 10includes a patient support surface or bed 100 with appropriate sideguards 102, mounted onto a bed base 104 with suitable supportingstructure 106, shown schematically. Bed base 104 includes a generallyY-shaped base frame 110 which includes outspread arms 112, 112 and astem 113, and wheels or casters 114 mounted to the ends of the outspreadarms 112, 112 and to a crosspiece 113 a at the end of the stem 113. Theoutspread arms 112, 112 are adapted to receive the mobile ventilatorassembly 12 therein, when the ventilator assembly is in its loweredcompact configuration, as is illustrated in FIG. 1.

A suitable mechanical latch 116 is located generally within the trougharea of the outspread arms 112, 112 and is employed for removablysecuring the mobile ventilator assembly 12 to the bed base 104. Asuitable cooperating latch mechanism 118 is located on the rear side ofthe ventilator 26 in a suitable location to mate with bed latch 116 whenthe ventilator assembly 12 is at the lowered position of FIG. 2. Whilethe cooperating latch 118 is illustrated as being mounted to a crosspiece (not shown) of the ventilator 26, it could just as easily bemounted to a cross-piece (not shown) of the base 20 of the ventilatorcart 18.

The bed 100 mounted to the bed base 104 generally includes suitableelectrical controls for varying the height of the bed 100 above a floorsurface by changing the attitude of the supporting structure 106. Inorder to prevent the bed 100 from being lowered onto the mobileventilator assembly 12 when same is docked to the bed base 104, there isprovided with the latch 116 a suitable switch 120 for disabling thishigh/low function of the bed 100. Most any suitable switch 120 could beutilized, and could be of, for example, the optical, mechanical orribbon type.

To provide for uninterrupted operation of the ventilator 26, a suitableDC power supply 122 is provided. While the power supply 122 could becontained within the ventilator 26, mounted to the ventilator cart base20, or could even be a part of the bed supporting structure 106, it ispreferably mounted to the bed base 110. Suitable cables 124 connect thepower supply 122 to the ventilator 26. Ideally, connecting cables 124 tothe ventilator 26 would immediately internally to the ventilator 26disconnect the AC power provided by the AC outlets 34 and immediatelyswitch the ventilator over to DC power supplied by the power supply 122.Cables 32 could then be unplugged from their respective AC ventilatoroutlets 34 thereby providing for continuous operation of and eliminationof any downtime associated with the ventilator 26 during transportationof the bed assembly 10 and ventilator assembly 12 to another location.

Referring to FIG. 2, it will be noted that the periphery of the bed 100when projected downwardly onto the floor therebelow defines a footprint126. As can be seen in the nested configuration, the mobile ventilatorassembly 12 falls well within this footprint 126. Therefore, a hospitalcare provider normally adept at maneuvering the critical care bedassembly 10 need not have to account for a larger footprint inmaneuvering the combination through doors, down aisles and intoelevators. The care provider can simply maneuver the critical care bedassembly 10 as before, and without the necessity of individually rollingthe mobile ventilator assembly 10 therebeside when transferring theequipment from one hospital room to another. Furthermore, the need tohurriedly transfer the equipment from one room to another and hence fromone wall AC source to another wall AC source is eliminated.

Other variations of a combination hospital bed and ventilator arecontemplated by the invention. For example, the ventilator could beseparated from its wheeled cart and docked to the hospital bed base, tothe supporting structure which mounts bed to base, or even the hospitalbed itself underneath a head section thereof. All such variations wouldprovide a hospital bed-ventilator combination, which combination isrollable as a single unit, with the ventilator being positioned withinthe footprint of the bed.

With reference to FIG. 4 there is illustrated a preferred embodiment ofthe ventilator cart of the present disclosure. The ventilator cart 150includes an outermost rectangular base frame 151 which has sides 152,153, 154 and 155. The cart 150 also includes an innermost rectangularsupport frame 156 which has sides 157, 158, 159 and 160. Innermostsupport frame 156 telescopes upwardly and downwardly with respect to theoutermost base frame 151. The outermost frame 151 has fixedly securedthereto a pair of standards or uprights 161 a and 161 b, the lower endsof which are fixedly secured to frame sides 154 and 155, respectively.Fixedly secured to each standard 161 a and 161 b is a vertical slide162, such as the type marketed under the trademark Accuride®.

Referring to FIG. 5, it can be seen that each vertical slide 162includes a plate 163 which is fixedly secured to a mounting block 164via fasteners 165. Plate 163 includes a pair of inwardly facing legs 163a. Block 164 is secured to the upper end of each of the standards 161 aand 161 b. Vertical slide 162 further includes a rail 166 which ismounted for vertical translational movement with respect to the plate163 via a number of steel balls 167 held within a vertically slidableball retainer 179. A strap 178 encircles the vertical extent of the ballretainer 179, has ends fixed to the rail 166 at a point approximatelymidway of the vertical extent of the rail 166, and is secured to theplate 163 at 163 b. Balls 167 in retainer 179 ride between the outersides of the legs 163 a of plate 163 and inwardly turned portions 166 aof rail 166. It will be appreciated that legs 163 a, balls 167 andinwardly turned portions 166 a effectively function as a linear ballbearing assembly. Rail 166 is itself secured to mounting bar 168 whichis, in turn, secured to a ventilator (phantom lines) via appropriatehardware 169.

At the upper end of each mounting bar 168 there is an ear 170 which isattached to the upper end of an air or gas spring 171. The lower end ofeach mounting bar 168 is fixedly secured to the sides 159, 160,respectively, of the frame 156. At the lower ends of each air spring 171there is provided a clevis 172 which is secured to the piston 173 of theair spring 171. The clevis 172 is pinned via a pin 174 to an ear 175 oneof which is located at each forward corner 176, 177 of the outermostframe 151. Legs 180 are provided for securing casters 181 to theoutermost frame 151.

A ventilator (phantom) to be secured to the ventilator cart 150 restsatop the innermost support frame 156 and is secured to the mounting bars168 via the fasteners 169. The angled orientation of the gas springs 171allows for proper vertical travel of a ventilator supported by the cart150, while simultaneously allowing one to physically overcome the forceof the gas springs in order to force the ventilator downwardly into anested configuration without any undue difficulty.

In order to actuate the gas springs 171 to raise the ventilator from itslowered position to its raised position, there are provided a pair oflevers 185 located beneath the forward side 152 of the outermost frame151. Each lever 185 includes a dog leg portion 186 which can be actuatedby a foot of a care provider. Dog leg section 186 is connected to alinear section 187 which terminates in a hooked portion 188. Hookedportion 188 is positioned directly underneath the actuating rod 190 ofthe gas spring 171. The levers 185 are supported within tabs secured tothe side 152, such as that shown at 192. Downward movement of the dogleg section 186 of each lever 185 causes upward rotation of the hookedportion 188, which actuates the actuating rod 190 of the air springthereby enabling a care provider to manually raise the ventilator aidedof course by the upward thrust of the gas spring 171.

It will be appreciated that the ventilator cart described herein can beused in any number of applications where a particular piece of medicalequipment is desired to be rollably transported and selectively raisedand lowered. Therefore, the cart is not to be limited solely for use inconjunction with ventilators and is claimed to have application to anynumber of different types of medical equipment.

With reference to FIGS. 6-11, and with like numbers representing likecomponents, there is illustrated a care cart 200 for use in conjunctionwith the critical care bed 10 and mobile ventilator 12. The care cart200 has a pentagonal base 201 with three casters 202 secured thereto forrolling the care cart 200 from place to place. A blow molded housing 203is mounted atop the base 201 and houses one or more batteries 204, abattery charger 205 and a compressor 206. A pair of posts 207, 207extend upwardly from the rear of the base 201, and a single post 208extends upwardly from the front of the base 201 approximately half thevertical distance of the rear pair of posts 207, 207. A platform 209 isconnected between the pair of posts 207, 207 and the single post 208 andis adapted to support four E-size oxygen and/or air tanks 216. Theplatform 209 has a transverse front support 210, a transverse rearsupport 211, and a plurality of longitudinal support rods 212 spanningbetween the front and rear supports 210 and 211, respectively. The rearends 214 of the outwardmost longitudinal support rods 212 a are securedto the rear pair of posts 207, 207 at 207 a. Forward transverse support210 is secured to the forwardmost vertical support 208 at 208 a. Therearwardmost transverse support 211 includes semicircular notches 211 awhich receive the neck portions 215 of oxygen and/or air bottles 216. Asemi-circular transverse support structure 217 is secured to theunderneath side of the platform 209 for supporting a custom air tank 218therein.

A shelf 219 projects forwardly from the upper ends of the pair of posts207, 207. The shelf 219 includes a rectangular cutout 220 along its rearedge which forms a gripping bar 221 which can readily be grasped by acare provider for pushing the cart 200 from place to place. Gussets 222are mounted between the shelf 219 and the pair of posts 207, 207 toprovide additional rigidity for the shelf 219.

A manifold 223 is mounted near the lower ends of the pair of posts 207,207. The manifold includes a plurality of connections 224 for connectingthe air and oxygen bottles 216 thereto, as with supply lines 225. Inorder to supply the ventilator 12 of the present disclosure with DCelectricity, air and oxygen from the care cart 200, supply lines 226,227 and 228, respectively are provided for connecting to anelectricity/air/oxygen controller box 240, which itself is connected tothe ventilator 12 (FIG. 8), the operation of which will be subsequentlydescribed.

With reference to FIG. 7, the care cart 200 is illustrated asapproaching the critical care bed 10 for docking under a foot sectionthereof. On the crosspiece 113 a of stem 113 there is pivoted a footactuated lever 229 which is employed for latching the cart 200 to thebed 10. Upon docking the cart 200 with the bed 10 the forwardmostsupporting post 208 enters into a concavedly cylindrical recess 213 inthe crosspiece 113 a. The lever 229 is then toggled upwardly as by acare provider's foot applying upward force to cross bar 229 a, whichupward toggling causes the lower end (not shown) of the lever 229 topivot downwardly and rearwardly of the support post 208 thereby securingthe support post 208 within the concavedly cylindrical recess 213 in thecrosspiece 113 a.

Numerous ancillary items can be employed with the care cart 200. Forexample, a drug box 230 can be incorporated on or into the shelf 219. Adisplay monitor 231 can likewise be supported on the shelf 219 fordisplaying patient care data during transport of the patient on the bed10 from one location to another.

With reference to FIG. 8, the care cart 200 is illustrated as beingfully docked to the critical care bed 10, supplying ventilator 12 withDC electricity, oxygen and air during transport of the bed 10,ventilator 12 and cart 200. It will be seen that the ventilator 12 andcart 200 nestably fit within the mobile footprint 126 of the hospitalbed 10. More particularly, and with respect to the care cart, it will beseen that platform 209 and shelf 219 are spaced apart vertically by asufficient distance such that clearance is provided for footboard 100 onthe bed 10. Therefore, when docked to the bed 10 (FIG. 8), platform 209underlies the foot end 10 a of the bed while shelf 219 overlies the footend 10 a of the bed 10. Further, it will be seen that stem 113 alongwith crosspiece 113 a on bed base 104 are spaced a sufficient distanceinwardly from the foot end 10 a of the bed 10 to allow the base 201 andsupporting platform 209 of cart 200 to completely come within footprint126 of bed 10 (FIG. 8).

Referring to FIGS. 9 and 10, there is illustrated another embodiment ofthe care cart designated by the numeral 300. The cart comprisesgenerally a base 301 including casters 302, four housing corner supports303 and a horizontal support frame 304 secured to the upper ends ofcorner supports 303. Base 301 and support frame 304 define a space whichis enclosed with a pair of pivoting end doors 305, 305, an upwardlyslidable, removable rear panel 306 and a forward panel (not shown). Sidedoors 305, rear panel 306 and the front panel are preferably of sheetmetal fabrication. Side doors 305, rear panel 306, front panel, base 303and supporting frame 304 define generally a housing 307 which includesan interior wall or divider 308 (FIG. 10) also of sheet metalconstruction. Divider 308 defines one compartment 309 which houses aliquid oxygen system 310 and another compartment 31 which housesbatteries 312 and a battery recharger 313.

Supporting frame 304 includes provision for supporting six E-size oxygenand/or air tanks 126 thereatop (FIG. 10), or alternatively a removableshelf 314 (FIG. 9) can be snapped atop the frame 304 to provideadditional shelf space in which case two E-size tanks 126 (FIG. 9) maystill be supported atop the remaining portion of the supporting frame304 which projects forwardly from underneath the shelf 314. A pair ofuprights 315, 315 extend upwardly from the rear corner posts 303 of thehousing and terminate in a forwardly projecting shelf 316, as in theprior embodiment.

Supported atop the supporting shelf 316 are a number of items employedin a critical care scenario, including a defibrillator 317, a drug box318, a portable suction unit 319, and a transport monitor 320. Transportmonitor 320 is powered by a tram 321 which, being a modular unit itself,is pluggable into a fixed monitor (not shown) in a typical critical carehospital room as part of, for example, a headwall unit or power column.The corners of the shelf 316 include I.V. pole sockets 322 therein suchthat I.V. poles 333 may be slipped therein, which support I.V. pumps 334and I.V. solution bags 334 a. Previously mentioned transport monitor 320is likewise supported on a pole 335 which fits into one of the sockets322 in the shelf 316.

In use, the care cart 200 or 300 of the present disclosure (theembodiment of either FIGS. 6-8 or FIGS. 9 and 10), is docked to the footend 10 a of a critical care hospital bed 10 and secured thereto with thefoot actuated lever 229. The DC electricity, air and oxygen lines 226,227 and 228 from the care cart are then connected to theelectricity/air/oxygen controller box 240 which is itself connected tothe ventilator 12 which is docked to the head end of the bed 10. Thiselectricity/air/oxygen controller box 240 controls the flow of air,oxygen, DC power and AC power to the ventilator 12 from the head wall atthe head of the bed 10 and the care cart 200 or 300 at the foot of thebed 10 during various stages of transport of the bed 10, ventilator 12and cart 200 or 300. The controller box 240 is located on the bed baseframe 110 adjacent the ventilator 12, and has three operating conditionsor scenarios.

In the first condition, with the controller box being connected tooxygen and air at the wall, both oxygen and air are supplied to thecontroller box from the wall at 50 psi. With no care cart docked to thefoot end of the bed, there is obviously 0 psi of oxygen and air suppliedto the controller box from the foot of the bed. The controller boxroutes 50 psi oxygen and air to the ventilator.

In the second condition, again with the controller box connected tooxygen and air at the wall, wall oxygen and air are again supplied tothe controller box at 50 psi. The care cart is now docked to the foot ofthe bed, supplying the controller box with 40 psi oxygen and air. Withthe bed in a stationary, semi-permanent position at the wall in thehospital room, the controller box closes the 40 psi oxygen and airsupply from the cart at the foot of the bed and again routes 50 psioxygen and air from the wall to the ventilator.

In the third condition, with the bed severed from its 50 psi wall oxygenand air during transport, the supply from the head end of the bed is 0psi. With the care cart docked to the foot end of the bed duringtransport, and supplying 40 psi oxygen and air to the controller box,the box routes the 40 psi oxygen and air supply from the cart at thefoot end of the bed to the ventilator, thereby supplying the ventilatorwith oxygen and air during transport.

The controller box further includes provision for routing AC and DC fromthe wall and care cart to the ventilator. When the bed is connected toAC at the wall, the box routes the AC to the ventilator which convertsthe AC to DC internally. When the bed is disconnected from AC at thewall, the box routes DC from the care cart to the ventilator.

After severing the bed from its AC electricity, oxygen and air supply atthe wall, then, the bed, ventilator and care cart may thereafter berolled about from place to place as a single unit by a care provider,normally by grasping the handhold built into the rear edge of the shelfof the care cart, the care cart providing total mobile support for theventilator and bed, and hence patient 4.

With reference to FIG. 11, and with like numbers representing likecomponents, there is illustrated yet another embodiment of the care cartof the present disclosure designated generally by the numeral 400. Inthis embodiment, the cart includes all of the features of the formerembodiments, with the additional feature of a motorized dolly or pilotjack 401 being included integrally with the care cart for motorizedtransport of the bed, ventilator and care cart. The pilot jack 401includes a handle 402 which can be pivoted transversely with respect tothe cart 400 for steering a drive wheel 403, which drive wheel ispowered by a suitable motor 404. Pressing button 402 a on handle 402activates motor 404 driving wheel 403 in a forward direction. Themotorized care cart 400 aids in overcoming the substantial increase ininertia generated by docking ventilator 12 and cart 400 to the bed 100.A suitable braking mechanism (not shown) would be incorporated withinthe cart 400 to aid in bringing the assembly to a stop. Preferably thispilot jack equipped care cart will be able to move 1500 lbs. of load andreach velocities up to 6 ft/sec. Preferably the pilot jack equipped carecart will have infinite variability in velocity control, including inboth the forward and reverse directions. Preferably electrolyte deepdischarge lead acid batteries will be used to power the pilot jack via apermanent magnet DC motor.

Other variations of the care cart are contemplated by the presentinvention. For example, other items can be incorporated into the cart inaddition to those illustrated in the Figures, and in particular in FIG.9. For example, a two-way communications system could be incorporatedwithin the care cart for communications between the care providertransporting the patient atop the bed 10 and, for example, a careprovider at the patient destination. Further, a lighting system could beincorporated into the care cart of the present disclosure to provideillumination for the care provider either for tasks to be performed on apatient or, for example, to light a hallway during transport of thepatient atop the bed 10 during, for example, power outage. Furthermore,the care cart of the present disclosure could be adapted to support aminiaturized ventilator, known as a “transport vent”.

The devices of the present disclosure have numerous advantages. Areduction in labor involved in preparing and transporting a criticalcare patient is effected. The total number of personnel required totransport a patient is reduced as well. The weight of the bed and theother devices utilized in conjunction with the bed is reduced whichminimizes the physical effort expended by care providing personnel. Thepatient outcome is improved by giving the same care to the patientwhether the patient is in the hospital room or in the hallway in transitbetween hospital rooms. And, all of the devices fit within the footprintof the bed to allow easy passage through doorways, around corners, andinto elevators.

With reference to FIG. 12, and with like numbers representing likecomponents, there is illustrated a motorized transport device or “mule”450 for motorized transport of the bed 100 with care cart 200 dockedthereto. Mule 450 docks to the generally Y-shaped base frame 110 of thebed base 104 within and between the outspread arms 112, 112, the framefor which can be fabricated of welded steel tubing or by casting of analuminum bronze alloy which is weldable to steel. When the bed 100 isused in conjunction with the mule 450, the mobile ventilator assembly 12is replaced with a miniaturized transport vent 563 which is supportedatop the care cart 200, for supplying patient 4 with oxygen and airduring transport. Additionally, care cart 200 can be adapted to supportan IV rack 560 which includes mounted thereto an IV pump 561 for pumpingIV solution from IV bags 562. As used herein, “bed” and “hospital bed”are deemed to generically embrace all rollable patient supports, such asstretchers, birthing beds, critical care beds, etc.

More particularly, and referring to FIGS. 12-20, the mule 450 has a base451 with a pair of casters 452, 452 mounted on its rear corners. At thefront of the base 451 and centered transversely of the base, there is anon-marking rubber drive wheel 453. Drive wheel 453 is located atapproximately the center-of-mass of the bed 100 and care cart 200combination. By so locating drive wheel 453, the bed 100 and care cart200 may readily be pivoted about the center-of-mass of the combinationwhen maneuvering the combination, thus facilitating transport of thecombination. Extending upwardly from the rear of the base 451 are a pairof handles 454, 454, the upper ends of each of which are outfitted witha hand grip 455 for gripping the handles 454, 454. Mounted on atransverse support 456 spanning between the handles 454, 454, is a joystick 457 of the wiperless type for use in controlling the drive wheel453. A cover 458 (FIG. 12) is removably secured atop the base 451,covering the components mounted thereon.

Referring to FIGS. 13, 18 and 19, base 451 includes longitudinallyoriented beams 451 a and 451 b which are fixedly secured together attheir forwardmost ends by a transversely oriented beam 451 c. Fixedlysecured to the forward transverse beam 451 c of base 451 is a drivewheel support structure designated generally by the numeral 460. Drivewheel support structure 460 includes an upper fork comprising a pair ofsupports 461, 461 and lower fork comprising a pair of supports 462, 462.The upper pair of supports 461, 461 have rear ends 461 a, 461 a whichare fixedly secured to the upper edge of transverse support 451 c ofbase 451. The forward ends 461 b, 461 b of support pair 461, 461 eachinclude a nylon wedge 463 secured thereto, the necessity for which willbe subsequently described.

Spaced underneath the supports 451 a, 451 b and 451 c is a rectangularframe 470 having sides 470 a and 470 b which are fixedly secured attheir forwardmost ends to forward transverse frame member 470 c. The aftends of the frame members 470 a, 470 b are fixedly secured to a reartransverse plate 471 (FIG. 12) which forms the rear edge of the base451, the transverse edges of which are fixedly secured to the handles454, 454. Gussets 472, 472 (FIG. 12) tie the rear ends of members 451 a,451 b into the lower ends of the handles 454, 454 above the casters 452,452. Fixedly secured to the underneath side of the frame 470 is a pan475. Supported atop pan 475 and within base 451 are a pair of batteries476, 476 which are employed to power a motor/gear box 477. The batteries476, 476 are preferably of the sealed, deep cycling type, and themotor/gear box 477 is preferably of the permanent magnet motor, helicalgear box type.

Drive wheel support structure 460 further includes a pair of verticalsupports 480, 480 each of which has upper and lower ends 480 a, 480 bfixedly secured to a respective one of the upper and lower horizontalsupport pairs 461, 461 and 462, 462.

Referring to FIGS. 13 and 18-20, drive wheel 453 is rotatably supportedon a shaft 485 the ends of which are supported in blocks 486, 486. Theends of shaft 485 pass through slots 487, 487 in the forward ends 462 a,462 a of lower support pair 462, 462. A screw 488 secures an end cap 482onto each end of shaft 485. A driven gear pulley 489 is 15 fixedlysecured to a cast iron drive wheel hub 483 with screws 484 and is drivenby a Poly Chain® belt 490, which passes over drive pulley 491 which isfixedly connected to the output shaft of the motor/gear box 477. It willof course be appreciated that slots 487 in the supports 462, 462 allowfore and aft adjustment of drive wheel 453 in order to adjust tension inbelt 490. Four allen head adjustment screws 492 adjust fore and afttravel of drive wheel 453, the bulkhead 493 in each of the support pairs462, 462 being mateably threaded to accept a screw 492. Lock nuts 494lock screws 492 against the bulkheads 493. The rearmost screws 492 andcorresponding locknuts 494 are accessed through a slot 506 in each ofthe supports 462, 462, whereas the forwardmost screws 492 andcorresponding locknuts 494 are accessed through an open forward end 507in each of the supports 462, 462 by removing its respective nylon wedge508.

On either side of drive wheel 453 there is a thrust washer 520, a needletype thrust bearing 521, another thrust washer 522 and a radial rollerbearing 523. In order to load these components in compression to takethe linear play out of these components along shaft 485, the end caps482 are tightened onto the ends of the shaft 485. With blocks 486, 486and hub 483 being slightly longer than the shaft 485, and as the caps482 are tightened with screws 488, shaft 485 is placed in tension andthe components on shaft 485 are placed in compression, thus removing anyaxial slop from the components on shaft 485. For adjusting shaft 485between supports 462, 462, a pair of allen head screws 524 pass throughone of the end caps 482 and bottom out against the side of thecorresponding lower support 462. Advancing screws 524 inwardly removesany axial play of the shaft 585 from between the supports 462, 462.

Referring to FIGS. 13-19, on the outer side of each of the lowersupports 462 there is a downward force generating mechanism 495 which,when the mule 450 is docked to the bed 100 generates a downward force onthe drive wheel 453 to prevent the drive wheel 453 from slipping on afloor surface upon being rotationally accelerated by the motor/gear box477. Each mechanism 495 includes an aluminum fork 496 which has a lowerend 496 a pivotally connected to the support 462. The upper end 496 bincludes a pair of spaced outside arms 497, 497, and a centermost arm497 a. A shaft 498 is fixedly secured to these arms 497, 497 and hasrotatably supported thereon two wheels 499 and 500. Wheel 499 isessentially a relatively thin aluminum disk, whereas wheel 500 is athicker nylon or glass filled nylon wheel. Pivotally supported to theshaft 498 between the wheels 499 and 500 and within slot 497 b of centerarm 497 a is the upper end 501 of the cylinder portion 502 of a gasspring 503. Each gas spring 503 is preferably sized at 200 Newtons. Thepiston portion 504 of the gas spring 503 has its lower end 505 pivotallysupported to the support 462. The distance between facing surfaces ofthe wheels 499 and 500 is sufficient to allow the upper end 501 of thecylinder portion 502 of the gas spring 503 to reside therein withoutcoming into contact with or otherwise binding up against the insidesurfaces of the wheels 499, 500 when the gas spring 503 is depressed.

Each of the mechanisms 495 generate downward force on the drive wheel453 when the mule 450 is docked to the bed 100, as the wheels 499 and500 of each of the mechanisms 495 roll underneath the bed base frame110, the operation of which will be subsequently described in moredetail.

Referring to FIGS. 13-19, a latching mechanism 510 is mounted on thedrive wheel support structure 460 and is operable to latch the mule 450to the bed base 110. The latch mechanism 510 includes three latchfingers: a centermost latch finger 511 and a pair of outer latch fingers512, 512. Each of the three fingers 511 and 512, 512 includes upwardlyramped forwardly presenting surfaces 511 a and 512 a, 512 arespectively, and radiused hook portions 511 b and 512 b, 512 brespectively. The outer latch fingers 512, 512 are fixedly secured to arotating sleeve 530 which rotates about a fixed shaft 531. Ahorizontally disposed bar 532 has rearwardly projecting handles 533. Thebar 532 is rigidly connected to the rotating sleeve 530 by verticallinks 534. The centermost latch finger 511 is itself rotatably connectedto the rotating sleeve 530 with its own rotating sleeve 535. Thecentermost latch finger includes an upstanding tab 536 with a cross pin537 press fitted therethrough.

Referring to FIGS. 14-17, there will be seen a mounting block 540 forconnection of the latching mechanism 510 thereto. The mounting block 540is attached to the upper side of the bed base 104 at the base of theY-shaped portion 110. The mounting block 540 essentially takes the formof a modified channel section having a bottom 541 and sides 542 andshort end walls 543, 543. A bar 544 is press fitted into holes in thesides 542, 542 and is positioned near one end of the mounting block 540.Slightly forward of the bar 544 there is an intermediate transverse wall545 having a height slightly less than the height of the cross bar 544.Wall 545 cooperates with the upwardly ramped forwardly presentingsurfaces 511 a and 512 a, 512 a of the centermost latch finger 511 andouter latch fingers 512, 512, respectively, such that forward movementof the mule 450 causes these upwardly ramped forwardly presentingsurfaces 511 a and 512 a, 512 a to ride up the wall 545 and to latchover the bar 544. Referring to FIGS. 15 and 16, it will be seen that thedistance between the radiused hook portion 511 b of the centermost latchfinger 511 and the axis of rotation of the sleeve 530 is slightlygreater than the distance between the hook portions 512 b, 512 b of thelatch fingers 512, 512 and the axis of rotation of the sleeve 530. Thisallows the centermost latch finger 511 to initially latch the mule 450to the bed 100, while further advancement of the mule 450 towards thebed 100 causes the outer latch fingers 512, 512 to then latch over thebar 544.

If the bed 100 is not loaded with a patient, the upwardly directed forceof the gas springs 503, 503 acting upon bed base 110 can cause the bedbase 110 to rise upwardly slightly. This slight upward movement of thebed base 110 requires a slightly longer latch finger, i.e., thecentermost latch finger 511, to successfully latch the bed 100 to themule 450, but when the bed is loaded up with a patient after thecentermost latch finger 511 is latched over the bar 544 there is aslight amount of play between the bar 544 and the radiused hook portion511 b (FIG. 16). Accordingly, the outer latch fingers 512, 512 act assecondary latching devices such that all play is taken out of theconnection between the mule 450 and the bed 100 after a patient isplaced atop the bed 100 and thus loading the bed 100. In addition, thecentermost latch finger 511 acts as a safety catch. This is because ofthe fact that when the rearwardly projecting handles 533 are depresseddownwardly (FIG. 17) (either purposefully or inadvertently), thuspivoting the outer latch fingers 512, 512 off of the bar 544, there is aslight rotational delay between when these outer latch fingers 512, 512disengage the bar 544 and when the centermost latch finger 511disengages the latch bar, due to the cross pin 137 catching upon theupper surfaces of the outermost latch fingers 512, 512 at which timecontinued upward rotation of the outer latch fingers 512, 512 causesupward rotation of the centermost latch finger 511 and hencedisconnection of the finger 511 from the crossbar 544.

To maintain the latching fingers 511 and 512, 512 in an approximatelyhorizontally attitude, tension springs 550, 550 have upper endsconnected to the crossbar 532 and lower ends indirectly connected to theupper fork supports 461, 461. A stop pin 551 is press fitted through thesupports 461, 461 and serves to limit downward rotation of the latchfingers 511 and 512, 512, under the force of the springs 550, 550.

Referring to FIGS. 18 and 20, outwardly projecting nylon wedges 508, 508inserted onto each end 461 b of each support 461 guide the latchingmechanism 510 onto the block 540, the wedges 508 directing the upperfork supports 461, 461 to the outer sides of the block 540. Initialentry of the mule 450 into the outspread arms 112, 112 of the bed base110 is facilitated through the use of nylon shoulder wedges 555, 555,one of which is mounted at either end of the transversely oriented beam451 c of the mule base 451.

Referring back to FIG. 12, an on/off key 570 is provided for powering upthe mule 450. An electronic fuel gauge 571 monitors the battery life inbatteries 476, 476. The aforementioned joy stick control 457 iselectrically connected to a pulse modulation controller circuit board575 which is in turn electrically connected to the motor/gear box 477,and employs current pulsing technology to control the velocity of themotor 477 via the joy stick 457. A battery recharger 576 (FIG. 13) isincluded on board for recharging the batteries 476, 476. A cord 572 iselectrically connected to the recharger 576 and is adapted to beconnected to an AC wall outlet for charging the batteries. When not inuse, the cord 572 is wrapped about a pair of cord holders 573, 573 whichare attached to one of the handles 454, 454. An amp meter 574 isviewable through the cover 458 for monitoring charge of the batteries476, 476 during recharging.

Mule 450 of the present disclosure could be utilized to move otherobjects in a hospital setting or otherwise as well. It could be used asa motorized transport for care carts, for example, or any other piece ofmedical equipment, or any rollable object, which has a base defining anopening into which the mule could dock. Accordingly, the mule inventionis not to be limited only to motorized transport of hospital beds.

Those skilled in the art will readily recognize numerous adaptations andmodifications which can be made to the present invention and which willresult in an improved combination nestable mobile ventilator, criticalcare bed, nestable care cart and nestable motorized transport, yet allof which will be within the spirit and scope of the present invention asdefined by the following claims. Accordingly, the invention is to belimited only by the appended claims and their equivalents.

1. A patient support apparatus comprising: a patient support frame; aplurality of casters; and a powered transport device including at leastone wheel and a motor, the powered transport device being positioned tolift at least a portion of the patient support frame and power movementof the patient support frame along the floor wherein the wheel of thepowered transport device is configured to move between first and secondpositions relative to the patient support frame, the portion of thepatient support frame being at a first height above a floor when thewheel is in the first position, the portion of the patient support framebeing at a second height when the wheel is in the second position, thesecond height being greater than the first height.
 2. The patientsupport apparatus of claim 1, wherein the plurality of casters includesat least four casters that are in contact with the floor when the wheelis in the first position.
 3. The patient support apparatus of claim 1,wherein movement of the powered transport device between the first andsecond positions is provided by manual power.
 4. The patient supportapparatus of claim 1, wherein the wheel is in contact with the floorwhen the wheel is in the first and second positions.
 5. The patientsupport apparatus of claim 1, wherein the powered transport device isspaced apart from the patient support frame when the wheel is in thesecond position.
 6. The patient support apparatus of claim 1, whereinthe patient support frame applies at least 400 Newtons force to thepowered transport device.
 7. A patient support apparatus comprising: apatient support including a patient support frame, a first pair ofcasters, and a second pair of casters longitudinally spaced apart fromthe first pair of casters, the patient support having a longitudinalcenter of gravity and a longitudinal midpoint positioned equidistantbetween head and foot ends of the patient support, and a poweredtransport device configured to power movement of the patient supportalong the floor, the powered transport device including a wheelpositioned to engage the floor to move the patient support relative tothe floor and a motor to power movement of the wheel, the wheel beingpositioned longitudinally closer to the longitudinal midpoint of thepatient support than to the first pair of casters, and the wheel beinglongitudinally spaced apart from the longitudinal center of gravity ofthe patient support wherein the powered transport apparatus isconfigured to lift a portion of the patient support frame from a firstheight relative to the floor to a second height relative to the floor,the second height being greater than the first height.
 8. The patientsupport apparatus of claim 7, wherein the combined longitudinal centerof gravity of the powered transport device and the patient support ispositioned between the wheel of the powered transport device and thehead end of the patient support.
 9. The patient support apparatus ofclaim 7, wherein the first pair of casters and the second pair ofcasters cooperate to define a caster footprint, and the wheel ispositioned within the caster footprint.
 10. A patient support apparatuscomprising: a patient support including a patient support frame, a firstpair of casters, and a second pair of casters longitudinally spacedapart from the first pair of casters, the patient support having alongitudinal center of gravity and a longitudinal midpoint positionedequidistant between head and foot ends of the patient support; a poweredtransport device configured to power movement of the patient supportalong the floor, the powered transport device including a wheelpositioned to engage the floor to move the patient support relative tothe floor and a motor to power movement of the wheel, the wheel beingpositioned longitudinally closer to the longitudinal midpoint of thepatient support than to the first pair of casters, and the wheel beinglongitudinally spaced apart from the longitudinal center of gravity ofthe patient support; and a care cart dockable with the patient support,the care cart being configured to support patient care equipment, thewheel of the powered transport device being positioned approximate atthe combined longitudinal center of gravity of patient support and carecart.
 11. A patient support apparatus comprising: a patient supportincluding a patient support frame, a plurality of casters, and alongitudinal center of gravity; a handle apparatus positioned adjacentto an end of the patient support to facilitate movement of the patientsupport; a wheel positioned to engage the floor at a positionlongitudinally between the handle apparatus and the longitudinal centerof gravity of the patient support; a transport frame configured tocouple the wheel to the patient support, the transport frame beingcoupled to the patient support frame at a location longitudinallyspaced-apart from the plurality of casters; and a motor coupled to thewheel to power rotation of the wheel.
 12. The patient support apparatusof claim 11, wherein the handle apparatus comprises a first verticallyextending portion.
 13. The patient support apparatus of claim 12,wherein the handle apparatus comprises a second vertically extendingportion.
 14. The patient support apparatus of claim 13, wherein thehandle apparatus comprises a support coupled to the first verticallyextending portion and to the second vertically extending portion. 15.The patient support apparatus of claim 14, wherein the first and secondvertically extending portions are positioned adjacent a head end of thepatient support.
 16. The patient support apparatus of claim 11, furthercomprising a control in communication with the motor to control thevelocity of the motor.
 17. The patient support apparatus of claim 16,wherein the control is positioned laterally between the first and secondvertically extending portions.
 18. The patient support apparatus ofclaim 17, further comprising a controller circuit board electricallycoupled to the control to receive an input signal therefrom andelectrically coupled to the motor to send an output signal to the motorbased on the input signal from the control.
 19. The patient supportapparatus of claim 11, further comprising a cord to provide electricpower for the motor and a cord holder defining a recess to receive thecord during storage.
 20. The patient support apparatus of claim 19,wherein the cord holder is coupled to at least one of the first andsecond vertically extending portions.